"while :" vs. "while true"

Bash

Bash Problem Overview

When you look at how infinite loops should be implemented, you mostly see this approach:

while :
do
  # loop infinitely
done

But I just don't understand the use of : here. Wouldn't it be better to use:

while true
do
  # loop infinitely
done

?

Bash Solutions

Solution 1 - Bash

from manual:

> : [arguments] > No effect; the command does nothing beyond expanding arguments and performing any specified > redirections. A zero exit code is returned.

As this returns always zero therefore is is similar to be used as true

Check out this answer: What Is the Purpose of the `:' (colon) GNU Bash Builtin?

Solution 2 - Bash

The colon is a built-in command that does nothing, but returns 0 (success). Thus, it's shorter (and faster) than calling an actual command to do the same thing.

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Solution 1 - BashphoxisView Answer on Stackoverflow
Solution 2 - BashunwindView Answer on Stackoverflow